Answer: A.
- A A
- B B
- C A ∩ B
- D the universal set
Correct answer: A. A
Explanation: A ∪ (A ∩ B) = A, the companion absorption law.
A Venn diagram makes set identities visual: A∪B is everything inside either circle, A∩B is only the overlap, and the region outside both circles represents the complement of their union - directly illustrating De Morgan's law (A∪B)′ = A′∩B′.
Concept context
Types of sets, operations (union/intersection/complement), relations, and types of functions with domain and range